Superconductivity in Sr₂RuO₄ was discovered 30 years ago. Among the many intriguing aspects of this unconventional superconductor is the picture of spin-triplet superconductivity, which could potentially carry both charge and spin supercurrents. This proposal was considered for a long time but was ultimately disproven in 2019. Despite intense research over the past several years, the superconducting symmetry of the archetypal unconventional superconductor Sr₂RuO₄ remains unresolved. Here we highlight the recent controversies and give a perspective of how the final resolution may be reached.

中文翻译：

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Sr2RuO4 中令人费解的 30 年超导性

Sr₂RuO₄ 中的超导性是在 30 年前发现的。这种非常规超导体的许多有趣方面之一是自旋三重态超导的图片，它可能同时携带电荷和自旋超电流。该提案考虑了很长时间，但最终在 2019 年被否决。尽管过去几年进行了大量的研究，但原型非常规超导体 Sr₂RuO₄ 的超导对称性仍未得到解决。在这里，我们重点介绍了最近的争议，并给出了如何达成最终解决方案的观点。